Pressure-compensation device for locomotive-engines.



H LENTZ. v PRESSURE COMPENSATION DEVICE FOR LOCOMOTIVE ENGINES.-

APPLICATION FILED OCT. 19, I914.

1,246,955. 7 Patented Nov 20, 1917. 2 SHEETS-SHEET I- v WITNESSES:

. I .INVENTCR 2 S BY v I ATTOR N EY'.

1,246,955, {Patel fined Nov. 20, 1917;

' 2 SHEETS-SHEET 2.

w men vi HUGO tea or HALENSEE, NEAR BERLIN, GERMANY.

PRESSURE-COMPENSATION DEVICE ron Loooivio'rivn-niic iivns. I

Specification of IZ-ettersl 'Patent.

Patented Nov. iilt.

Application fiIedOctober 19, 1914. Serial No. 887,520.

T 0 all whom it may concern:

Be it known that I, HUGO LENTZ, a' citizen of the German Empire, and residing at Halensee, near Berlin, Germany, have invented certain new and useful Improvements in Pressure-Compensation Devices for Locomotive-Engines, of which the following is a specification.

My invention relates to locomotive engines, and it is especially useful with such engines having puppet valve gearing. A. primary object of the invention is to provide pressure compensation means for such engines for use when starting or when running light; and in the preferred form of my invention I accomplish both of these objects, 2'. e., the pressure compensation in starting or in runing light, with the same device. Vhile my invention is particularly adapted for use in connection with locomotive en gines, it will be understood that it is useful 1 in connection with any engines in which this pressure compensation may be desired.

In the preferred form of my invention I arrange, immediately adjacent to the inlet valve cam, a suitably operated auxiliary cam which is so formed that when it is rocked into one or the other of two positions, one or the other of the inlet valves are lifted and steam is able to enter the corresponding side of the cylinder up to full admission, while when it is rocked to a. third position it lifts both valves, moves the antifriction rollers of the valve-rods out of reach of the cams controlling them and thus, when the engine runs light, brings about an equalization of pressure at the two sides of the piston.

To this end my invention consis s'in the novel construction, arrangement and combination of parts described hereinafter and pointed out in the claims. One illustrative embodiment of my invention is represented by way of exa'mple;in the accompanying drawings, wherein Figures 1 and 2 are longitudinal section and side elevation, respectively, of a valvegear casingof the inlet and outlet valves;

Fig. 3 is a longitudinal section through the valve gear casing of the inlet valves,

' ing faces n. located on the same side Fig. 4 is a section taken on the line in Fig. 3,, V

Fig. 5 is a horizontal section taken on the line 5-5 in- Fig. 3, and Figs. 6 and 7 are views similar to that shown in 4 (a part of the apparatus of said figure being broken away) and showing the special cam in different operative positions.

Referring firstly to Fig.1, the letter a designatesithe cam shaft for the exhaust valves of the engine. This is tightly inserted by means of a bushing 6 into the casing 0 and carries at its inner end the cam a which coactsin known manner with the exhaust valve-rods mounted in the holes 0. On the outer end of the cam shaft (1 is mounted a lever m, pivotally attached to which is a rod, not shown, connected to any suitable reversing gear. 7

The casing d for the inletvalve gear is arranged above the exhaust valve gear casing 0. The bushes 9 containing the inlet valve-rods f (Fig. 4) are inserted in this casing d. The endsof the valve-rods f are provided in the usual manner with anti-. friction rollers h with which the cam 70 on the cam shaft la coacts. A sleeve Z is slipped free to rotate over the cam shaft 70,- both parts being inserted steam-tight into the casing cl by means of a bushing 2'. The inletvalve cam shaftlc is driven positively by the shaft a by means of the lever transmission 70', e, a, so that the inlet and exhaust valves can be suitably moved by means of the lever m by the link.

The valve rod engaging member of my improved pressure compensation device, which member is in the form of a cam n is arranged on the above-mentioned, axially rotatable'sleeve Z, and it can be adjusted by the driver by means of the lever Z firmly connectedwith it by a key Z The device as used for starting will first be described. The end of this sleeve adjacent to the cam 76 carries the cam disk at providedwith several p'ojections which, as Fig. 5 shows, ca n coact with the ends 7 of the valve rods f. Starting from the middle position I (Fig. a of the. lever I this cam disk n hastwo risof the axis of the valve rod. By moving the lever Z out of its middle position I in either direction one of the valve .rods is lifted, as shown in Fig. 6, and with it the corresponding inlet valves r, so that live steam can enterthe corresponding end of the cylinder. The arrangement is such that, when start ing, the link is adjusted to the maximum cut-off, say 60%. If this cut-off does not sutiice for ing the lever Z about its middle position I the driver can make the admission independ ent of the position of the lever.

My invention also provides means for effecting pressure compensation when the engine is running light, and in the present embodiment of the invention this pressure compensation is attained by suitable cam portions or surfaces formed on the said cam disk 12; the one projection n of the cam disk 11, is lengthened toward the rear and thus forms a larger projection 0, to which a second diametrally opposite projection 0 corresponds. When the lever Z is moved into position II the tips of these projections 0' and 0 engage with the ends of the valve rods and are held by notches 7" as shown in Fig. 7. In this position of the projections 0 and 0 both valves 1- are lifted and a connection between the two sides of the piston is thereby established. This adjustment is effected when the locomotive runs down hill without steam. A constant equalization of pressure then takes place between the two sides of the piston, and consequently all injurious and power-consuming compression in the cylinder is avoided.

lVhile I have described and illustrated the preferred form of my invention, it will be obvious to those skilled in the art, after understanding my invention, that various changes and modifications may be made therein without departing from the spirit or scope of the invention, and I do not wish to be understood as limiting myself other than as indicated in the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a device of the character described for use with an engine having inlet puppet valves, the combination of said inlet valves, controlling the admission of steam at each end of the cylinder, a cam shaft having a cam thereon normally operating the valves,

spindles from the valves extending toward the shaft, and means including a cam member adjacent said valve cam to engage said valve spindles to open the valves and render said first valve cam ineffective to control the valves, so as to equalize pressure at each end of the cylinder.

2. In a device of the character described, the combination of inlet valves and spindles extending therefrom, means including a cam starting the locomotive, by rocl and a cam shaft for opening and closing the valves under normal operation of an engine, and means including a part shiftableabout the axis of the cam shaft and adapted to operatively engage the valve spindles to hold the valves open when they would otherwise-be operated under the control of said cam, said valve-holding means being under the control of the engine driver to be operated at will.

3. In a device of the character described, the combination of inlet valves, means including cam mechanism having a regular sequence of operation for opening and closing the valves, and a device separate from the cam mechanism and operatively related to the valves for momentarily holding one or the other of the valves open to vary the cut off from that under normal operation of the valves when operated by the cam mechanism, said device being operated independently of the movement of the cam mechanism.

4. In a device of the character described for use in connection with engines having puppet valves, the combination of said. valves, means including a cam shaft and cam having a regular sequence of operation for opening and closing the valves, and means including a part shiftable about the aXis of the cam shaft for holding the valves open during the sequence of operation of said cam means to balance pressure in the engine in running light.

5. In a device of the character described for engines having puppet valves, the combination of said valves, means including a rocking cam member for operating the valves, and means adjacent said rocking cam member and operatively related to the valves for holding the same open during the rocking movement of said cam member, said means being brought into play at the will of the engine driver to balance the pressure in the engine in running light.

6. In a device of the character described, the combination of inlet valves, means including a cam shaft and cams for opera tively controlling the said inlet valves under normal operation of the engine, and means separate from said cam mechanism and operated independently thereof and under the control of the driver and operatively related to the valves to render said first means momentarily ineifectual to control one of said valves, whereby mav be altered independently of the setting of the first means.

7. In a device of the character described, the combination of inlet valves, means including a rocking cam shaft and a cam for operating the valves, and means operatively related to the valves and of the engine driver to be moved at will in dependently of the rocking cam shaft into positions to hold one or the other of the the point of cut-off under the control valves open to vary the point of cut-off of the engine.

8. In a device of the character described, the combination of an engine having puppet valves, means including a rocking cam shaft and cam for opening and closing the valves, and a second cam operatively related to the valves to be shifted into position to hold one of the same open independently of the position of the first cam member, and means under the control of the driver of the engine for shifting said second cam at will to vary the cut-off.

9. In a device of the combination of inlet valves, means normally controlling the operation of said valves, and shiftable means operatively related to said valves and under the control of the engine driver, and having provision for opening one or both of said inlet valves, depending upon whether it is shifted in one or another position by the driver.

10. In a device of the character described for engines having puppet valves, the combination of said valves, means including a rocking shaft and cam for operating the valves, and rocking means having cam surfaces operatively related to said valves and having means for controlling the same at the will of the engine driver, whereby said cam surfaces may be rocked into position to hold one of said valves open to vary the point of cut-ofi, or rocked into position to hold both of said valves open to equalize the pressure in the engine.

described 11. In a device of the character for engines having puppet valves, the com bination of said valves, means including a rocking cam shaft and cam, spindles from the valves extending toward the shaft and adapted to have their inner ends engaged by the cam, a sleeve surrounding said rocking shaft and having a cam member adjacent the valve-operating cam, and means connected to said sleeve and under the control of the engine driver for rocking the sleeve to move the cam member thereon in position to engage one or more of the valve the character described,

spindles to open the valve or valves independently of the operation of the first-mentioned cam.

12. In a device of the character described for engines having puppet valves, the combination of said valves, means including a rocking cam shaft and cam, spindles from the valves extending toward the shaft and adapted to have their inner ends engaged by the cam, a sleeve surrounding the rocking shaft and having means for rocking the same under the control of the engine driver, said sleeve having a cam member at one end in operative alinement with the valve spindles, said cam member on the sleeve having diametrically arranged cam projections for engaging the valve spindles when for end in operative the sleeve is rocked in oneposition and having two cam surfaces arranged on one side of an axial plane through the sleeve for engaging one or the other of the spindles when the sleeve is shifted in another position, whereby said sleeve cam member may be operated to open both valves to equalize the pressure in the engine or to open one or the other valve to vary the cut-off.

13. In a device of the character described, the combination of an engine having puppet valves with spindles extending therefrom toward each other, a housing into which the adjacent ends of the spindles project, a bearing detachably secured to one end of said housing, a sleeve journaled in said bearing and extending into the housing and having means at its outer end for rocking it, a cam member at the inner end of said sleeve arranged in operative alinement between the adjacent ends of the valve spindles and having cam surfaces adapted to engage the spindles when the sleeve is rocked to hold the valves open, a camshaft journaled in the sleeve and extending therethrough into the housing and having a camat its inner alinement with the spindles for operating the valves, and means connected to the outer end of the cam shaft for rocking the same to operate the valves in normal operation of the engine. I

14. In apparatus of the character described, the combination of an engine having puppet inlet and exhaust valves, means including rocking cam shafts and cams for operating the inlet and exhaust valves, means for rocking one of said cam shafts, link mechanism connecting said cam shafts whereby the other is rocked in proper sequence therewith, a sleeve surrounding the cam shaft for the inlet valves, and means for rocking said sleeve independently of the movement of the cam shafts, and a cam member on said sleeve operatively related to the inlet valves for opening the same independently of the operation of their cam shaft.

15. In a pressure compensation device for locomotive engines, having puppet valve gear and rocking cams, for use when starting and running light, the combination with an inlet valve cam of a manually operatable auxiliary cam (42) adjacent thereto having two lifting faces (1%) arranged on the one side of a diameter and two larger projections (0, '0) diametrally opposite one another, substantially as shown.

16. In a pressure compensation device for locomotive engines, having puppet valve gear and rocking cams, for use when starting and running light, the combination of a shaft, an inlet valve cam thereon, a sleeve slipped over the shaft up to said cam, an auxiliary cam on the end of the sleeve adjacent to the inlet valve cam, a casing surrounding the shaft, cams and sleeve, and a bushing for making the joint between the ture in the presence sleeve and the casing steam-tight, said auxiliary cam having two lifting faces (12) arranged on the one side of a diameter and two larger projections (0, 0) diainetrally opposite one another, substantially as shown.

Witnesses Gopies of this patent may be obtained for five cents each, by addressing the Washington, D, 0..

In testimony whereof, I afix my signaof two Witnesses" HUGO LENTZ HENRY HASPER, VVOLDEMAR HAUPT.

"Commissioner of Patents, 

